Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

For the last few weeks, I've been using the 2000 watt, Hyundai inverter generator at camp to provide electricity in light load applications.  Basically a 42" LED LCD TV, a Bell Receiver and a couple compact flourescent lights.   Less than 300 watts in total.   Initially I had just back fed the generator into the camp using a 12 ga. 50' extension cord.   After discovering that supplying that outlet also supplied limited power to the garage, I decided to try relocating the generator the 110 ft. or so from the camp to the garage.  I back fed the extension cord into an outlet at the garage and it powers all of the same circuits as the outlet on the camp did. 

The main power line from the garage to the camp is large diameter Tek cable (00 or 2/0) and is rated for around 195 amps so resistance should be minimal.   There is a very short eight feet of 14 ga. wire from the outlet to the main fuse box which controls the power from the large diesel generator to the main power line.  Now that I've explained the physical set up, my question is whether or not the additional distance of 120 feet or so of heavy wire transmission would put more demand on the small generator? 

The reason I ask is that I noticed what seemed to be a slight increase in fuel consumption with the exact same load.  Can't say for sure because I've only taken one fuel consumption reading from the new location. The fuel consumpiton variance was minimal.  I was getting a spectacular consistent 3 hrs./litre of fuel with the generator feeding directly into the camp.  The new location gave me a measurement of 2.79 hrs./litre.  

I know the numbers are insignificant and might just be a measurement variance, however, I'm still curious.  Does increasing the distance from the generator, despite the line having minimal resistance, increase demand on the generator?     

borat wrote:

BORAT Just want to make sure I'm following you correctly. When you say "2.20 hours" do you mean 2.20 hours which = 2 hours and 12 minutes OR are you saying 2 hours 20 minutes??

I'm back in town now and don't have the figures with me.  If I recall correctly, I measured 8.7 hours run time on close to 4 liters of fuel.  That works out to 2.175 hours per litre wich I rounded off to 2.2 hrs/liter.  Which is approx. 2 hrs. 12 minutes.  

I know I'm pretty much splitting hairs now but I suspect that my measurements are a bit conservative.  During the 8.7 hours, some of it was under 1000 to 1500 watts of load.  Maybe a total of ten minutes or so.  In addition to that, when I refueled I probably squeezed in a few more oz. than normal, which would skew measurements a bit.   I plan to try to be as consistently exact as possible when refueling to get an accurate base line.  However, I'm confident that under my normal light load of 500 watts or less, I should see 2.5 hours per  litre.   Which is considerably better than the 1 litre of diesel fuel per hour  I was burning to run the Kubota powered 6K watt  generator.  

If the Hyundai holds up for five years or more, it will easily pay for itself in fuel savings as well as reducing oil change costs.   I go from using 4.6 litres of oil for the diesel to less than half a litre for the Hyundai and the recommended hourly duration for the Hyundai is the same as the 100 hrs. I was changing the diesel at.  That equates to almost ten oil changes for the Hyundai for each Kubota oil change.   At approx. $30.00 for oil and filter for the diesel oil change, it doesn't take too long for the Hyundai to pay for itself providing it lasts.   Considering that most of it's life will be spent  loafing along at approx 2000 rpm, in a clean environment, I suspect that it should hold up reasonably well with proper maintenance.  

Reducing fuel and oil consumption is also ecologically much more friendly.  I like that.

Overall I'm pretty happy with this little generator.   When we have it running  up at the garage location, it's so quiet that we forget that we've got a generator running.  Very pleasant indeed.  

Would anyone know approximately what the engine rpm operating range would be for an inverter generator?   I know the Hyundai's uppper engine rpm is 5500 at full load.  However, I'm a bit confused with the lower engine no load speed despite measuring it with the Sirometer.   I get strong readings at 1700 and 3400 rpm at no load.   My ears tell me that it's running pretty slow and I'm thinking 1700 rpm.   Would anyone know for sure what the lower no load rpm range is on inverter generators?

I have a small Yamaha Inverter. I bought it used but recall getting the manual with it. I'll see if I can find it and post if I find anything in the specs.

Information on the lower rpm operating range for inverter generators is difficult to find. 

I've done a fair amount of searching and found a forum that had some good info on inverter generators.   I learned that inverter generators run at two speeds only "Eco" mode (low speed) and full load speed.   I was under the impression that inverter generators could regulate engine speed to suit load requirements.  That assumption was wrong.  When the demand on the generator exeeds the power being delivered in Eco mode, the generator opens to max throttle to meet the additional demand.  It was suggested that the lower rpm range is usually half of full load operating rpm.  If that's the case,  the Hyundai continous max. load rpm is 5000 rpm, accordingly lower rpm speed should be 2500 rpm.   I cannot confirm nor dispute this info. however, my rpm measurements tell me otherwise with the Hyundai being either 1700 rpm or 3400 rpm.    

Considering the prominence of electronic fuel injection in many small engines such as those found on late model ATVs, motorcycles etc. one has to question why this technology has not been integrated with inverter generators?  It would simple enough to "map" a sliding scale on the EFI to match engine rpms to generator demand.  Seems like a no-brainer to me.  The efficiency gains would be substantial.      

borat wrote:
One element electronic fuel-injection systems require is a battery or some source of power to energize the electronics before the engine can be started. Not a big deal on say a 3kw unit that already has electric start and has a battery, but for small portables (2.5kw and below) that are only recoil start, it could be a real engineering challenge. A battery (and electric start) adds significant weight too, and nobody in sales / marketing wants a portable generator to gain any weight.

With the issues carburetors have these days with ethanol fuels, there's little doubt fuel-injection will eventually work its way into small gas engines and power equipment. Hang on.

-Robert@Honda
Caveat: I work for Honda, but the preceding is my opinion alone.

Good points. 

Wouldn't take too much of a battery just to power the fuel injection until the generator kicked in and there wouldn't be a starter/solenoid involved to add weight.  I'd say it's probably not too far off in the future.

That hasn't been my experience with my EU2000i's. I have a tach on mine and RPM varies throughout the range with varying loads with ECO on. 3K RPM idle speed with ECO on and 4300 RPM with ECO off. I think if you push gen on upper limits it will goto 5K but I never go there. borat wrote:

snowmachine wrote:
I should wire up an electronic tach to see how the Hyundai behaves.  

I've got around 90 hours on it now and it's been flawless.   That's hardly an endorsement for longetivity, however, if something was amiss when it was built, it likely would have let go by now.   For such an inexpensive little machine, other than the weight factor, I'm very happy with it's overall performance.   If I get 1000 hrs. out of it, the machine will have paid for itself many times over just in fuel and oil change savings.  

If for some reason it doesn't last, I'll definitely look at a Yamaha or Honda inverter generator.   Small inverter gensets are just so quiet and easy on fuel compared to my big Kubota diesel powered machine.   If I do get an new machine, it will likely be a bit larger and with electric start to make it easy for the wife to use. 

Took an electronic tach out to camp to measure rpm vs. load.  I discovered that the change in rpm seem to be incremental.   Low speed is around 3150 rpm, bump up the load and the revs jump to around 4500 which is still 1000 rpm lower than max.   Rpm change doesn't appear to be very linear.  It just seems to have low speed in eco mode of 3150, medium-high speed 4500, hight speed of 5000 then full out high speed for surge load of 5500 rpm. 

In eco mode, fuel consumption has been consistently in the 2.5 hrs./litre range.  Very impressive.  Performance has been flawless.  Starts easily, doesn't use any oil, and from where it's located, virtually silent. 

What I did discover however is that the fuel capacity of 7 litres quoted in the manual is dead wrong.   After ten hours of operation, the machine stopped running due to being out of fuel.  At 2.5 litres/hr in eco mode, the machine should have run for 17.5 hrs.  I refilled the machine to capacity then drained the fuel tank into a precise measuring container.  The tanks hold 4.3 litres.   Considering that it's in a static location, I could easily attach an auxilliary fuel tank if I wanted.  However, we only average about 4 to 5 hours of run time a day and it's no big deal to refill it.   Other than that little surprise, I have to say that for the money, this is an excellent little generator.